1. Field of the Invention
The present invention generally concerns the organization, packaging and optimization of reverse osmosis water purification systems, particularly for installation and use in kitchens, particularly including restaurant kitchens.
The present invention particularly concerns water stations, or cabinets, or consoles incorporating both (i) a reverse osmosis water purification system and (ii) a sink.
The present invention further particularly concerns a reverse osmosis system having both an atmospheric storage tank completely contained in a cabinet, and a pressurized auxiliary storage tank remote from the cabinet, for storing purified water.
The present invention still further particularly concerns a reverse osmosis system having quick-change sediment filters that are changeable while the system is operating.
2. Description of the Prior Art
2.1 An Increasing Need for Purified Water in Cooking, Particularly in Oriental Cooking, Particularly of Rice, Including in the Orient
As world population density and industrial activity simultaneously increase, ever greater amounts of ever more marginally impure water is required to be rendered potable for human use, including use in cooking, by water treatment. Even advanced industrial societies have been forced by ever increasing demands for potable water into the capture and use of marginal surface and subsurface waters that require extensive purification treatments. These treatments, most notably including chlorination, may impart a slight taint, or taste, to the water so treated. Although these treated waters are presently presumed safe for human consumption, they may impart a slightly undesirable taste to foods when used in cooking.
In some more affluent areas of the world, including in the United States, the use of bottled water both for cooking and for consumption by ingestion (i.e., drinking and the eating of re-hydrated foodstuffs) has become common in some areas, especially in those areas where local natural waters retain a pronounced taint even after treatment. According to the International Bottled Water Association based in Virginia, U.S.A., the United States national consumption of bottled water increased from 1.1 billion gallons in 1985 to 2.7 billion gallons in 1995. The consumption is, however, regionally very uneven. California alone consumed 788.2 million gallons of bottled water in 1995. Some consumption of bottled water is attributed to motivations, such as fashion, other than (i) necessity, (ii) taste, or (iii) health. However, there is ample evidence that at least a wealthy society (such as the U.S.) will sometimes, and in some places, pay handsomely for pure water, even to the astronomical levels (in California, U.S.A., circa 1996) of paying twice as much for a liter of water as for a liter of gas.
Appreciation of pure water is not limited to wealthy, nor to occidental, societies. Indeed, western, or occidental, cuisine is generally not so water intensive as is oriental cuisine, especially such oriental cuisine as is based on the consumption of rice. It will, of course, be recognized that a greater portion of the world's people subsist primarily on rice than on any other grain. In particular, more than fifty liters (50 l.) of water may be used in the preparation and cooking of a single (one) kilogram of rice. Other major oriental foods such tea, soups and tempura batter also use large amounts of water. This copious use of water in the preparation of rice, and of other foods, in oriental cooking effectively precludes any cost-effective usage of bottled water.
Nonetheless to a lack of any appreciable use of bottled water in the home and commercial kitchens of the orient, it has as of late been recognized that the quality of municipal waters in the major cities of, for example and most notably, Japan has, despite water treatments of the most advanced order producing water of undisputed safety for human consumption, presently arrived at a level where taste components of treated water can at least be detected (if not directly tasted, or distinguished, or identified) in cooked foods, notably rice. The Japanese, in particular, are very fastidious about the quality of their rice, paying significantly premium prices for the finest grains. It is obvious that the taste of even the finest rice can be impaired if the rice is cooked in water that imparts any undesired tastes.
According to the recognition that the cooking of rice could be improved, at least in selected areas of present day metropolitan Japan, by the use of purer water, Mr. John Lai of Tokyo, Japan, has reportedly proceeded to the investigation of, and to the filing(s) of the application(s) for patent(s) on, improved methods for the cooking of rice using, at least in part, water that is purified by process of reverse osmosis.
It has been, in particular, the insight of Mr. Lai that the first washing of uncooked, natural, rice should transpire with purified water--such as is preferably obtained by process of reverse osmosis conducted on municipal supply water. A normal second and third washings of the rice then preferably transpire by use of only normal, tap, water or, at most, by use of filtered tap water. Finally, the washed rice is preferably cooked in water that is again purified by process of reverse osmosis.
The utility in using purified, reverse osmosis, water ("RO water") in the first and last steps is to both initially, and finally, permeate the rice grains with the purest water available. Intermediary steps are less critical, and are suitably conducted with tap water (or filtered tap water) to avoid the water wastage attendant upon the production of purified water by process of reverse osmosis.
The rice so washed and cooked is reportedly of a detectably better quality than is rice washed and cleansed solely by the use of municipal, tap, water (at least in certain areas of Japan where tens if not hundreds of millions of people live and eat). The superior quality of this rice is of particular concern to (Japanese) restaurants, which understandably wish to compete for their discriminating clientele by offering cooked rice--a universally-recognized and appreciated basic food--of the best quality possible.
Preliminary indications are that the clientele of at least one Tokyo restaurant operated by Mr. Lai may have ratified their approval of rice prepared with water purified by process of reverse osmosis in a most profound way: they eat more of it. Indeed, indications are that the ratio of the restaurant consumption of rice prepared with purified water to rice not so prepared is unexpectedly high (at least in Tokyo, Japan), and may be as high as several times greater.
Additionally, there have been unexpected indications that some foods prepared with purified water, notably tempura batter, may have a longer usable life, and may correspondingly be prepared in larger batches with increased efficiency, when made with purified water. Food chemistry is complex, and it is uncertain as to what effect is being observed, and to what magnitude and consequence, during the use of purified water particularly in oriental cooking. However, it goes without saying that few, or no, recipes call for the intentional addition of calcium carbonate, or other metals and minerals removed from water by reverse osmosis, to foods during cooking. It therefore makes some sense, which is presently in process of investigation, that the use of pure water may have unexpected beneficial consequences (other than just taste) to the preparation of food.
Nonetheless to the desirability of using water that is purified by reverse osmosis in the (i) washing and (ii) cooking of rice in Japanese restaurants, use of reverse osmosis (RO) water incurs at least two challenges. First, the total amount of water used in the preparation of one liter (1 l.) of rice by partial use of purified RO water is even higher than the normal large amount. Commonly ten liters (10 l.) of purified, RO, water plus eighty liters (80 l.) of tap water, or a total of ninety liters (90 l.) of municipal water, are used in the washing and cooking of each liter (1 l.) of rice. Second, the home and restaurant kitchens of Japan are exceedingly small by occidental standards, and there is scant room for the installation of any reverse osmosis water purification system having the desired capacity.
It will be recognized that the challenges of volume delivery of pure water, and accommodation to existing restaurant kitchens, that may be most acute in oriental kitchens are not limited to these kitchens. Indeed, occidental cuisine can also benefit from the use of pure water in cooking, and space is also at a premium in existing occidental restaurant kitchens which are generally compactly laid out (as are oriental kitchens) for reasons of operational efficiency.
2.2 A Desirable Integration of A Reverse Osmosis Water Purification System Into the Crowded Kitchens of, Inter Alia, the Orient and Japan, and, in Particular, Into the Existing Kitchens of Oriental Restaurants, Is Challenging
The reverse osmosis system of the present invention will be seen to be unique for being suitably retro-fitted to existing kitchens, particularly restaurant kitchens and more particularly the crowded kitchens of oriental restaurants including as exist, inter alia, in the orient, and most notably in Japan.
The biggest problem faced with installing any new equipments, including reverse osmosis system equipments, in such existing oriental kitchens is space. As the awareness for the need for water purification in the Japanese restaurant industry grows, the motivation of restaurant owners and operators to install a reverse osmosis water purification system is expected to increase to considerable levels. However, the installation of a restaurant RO system is often strongly limited by the existing physical constraints of the restaurant's kitchen, and of its plumbing (and, to a lessor extent, its electrical wiring). Even should room for a RO system be found in a restaurant kitchen, access to the installed RO system for purpose of maintenance must be provided.
It will momentarily be seen the present invention adopts a usage, particularly in restaurant applications, of the existing volume, and of a part of the "air space", normally occupied by the kitchen sink. Every kitchen must have a sink to wash hands, rinse vegetables, wash pots and pans, etc. It will momentarily be seen that, in accordance with the present invention, a RO water purification system and a sink are combined to accomplish both the (i) water supply, including a purified water supply, and the (ii) sink, needs of a restaurant kitchen.
It will momentarily further be seen that the unique design of the combined sink and RO system of the present invention will, while performing a substantially normal process of water purification by process of reverse osmosis, occupy as much as six to eight cubic feet (6-8 ft.sup.3) less volume than would normal RO system equipments. Such normal RO system equipments would include, as separate parts, any of (i) one or more sediment filters, (ii) one or more carbon filters (of wall mount or of floor mount design), (iii) one or more reverse osmosis membranes, (iv) a purified water storage tank (either atmospheric or pressurized), and (v) a RO water delivery system. Any RO system must also include piping or tubing to connect all of the component pieces together so as to make the RO system functional.
The preferred embodiment of a combined (i) RO water purification, and (ii) sink, system of the present invention will momentarily be seen to realize, by very judicious and creative tight packaging, both the functions of (i) pure water supply, and (ii) used water evacuation, in a single cabinet. The preferred cabinet does not, by and large, take up any more nor any additional floor space, and occupies but only modestly more volume, than is presently occupied by a restaurant sink and its associated plumbing and support structure. The water station, or cabinet, or console, of the present invention can typically be installed into the existing volume of a sink, particularly the typically large sink of a restaurant.
2.3 A Reverse Osmosis Water Purification System Integrated Into a Kitchen Would Desirably Not Waste Water
A reverse osmosis water purification system integrated into an oriental restaurant kitchen would normally be used to produce copious amounts of purified water, typically up to eight hundred gallons (800 gal., or 3061 liters) per day. Such a system would desirably not waste water. Wastage of water is, by and large, a function of two different criteria: 1) how much water it takes to make each unit volume of the purified, RO, water, and 2) any usage that is made, or that can be made, of the RO waste water.
Considering the first criteria, the RO system in accordance with the present invention will momentarily be seen to employ such a diversion of waste water back into the purification cycle as ultimately supports a very high ratio of one to one (1:1) between the produced purified RO water and the waste water. Although such a "re-circulation" path is known, its (i) components, and (ii) required plumbing, in the system of the present invention are to some degree in tension with the requirement of the system to be packaged as extremely compactly as is possible.
Considering the second criteria, a RO water purification system must normally flow connect across an air gap (as is mandated both by plumbing codes and by good plumbing practices) to a drain for the evacuation of waste water. It will momentarily be seen that the RO system in accordance with the present invention will, when installed in the space conventionally occupied by a sink, suitably use the existing drain connection (as well as the incoming water supply) of the sink. This usage will, however, present certain challenges that have, as will shortly be seen, to do primarily with the prevention of any back-up of effluent into the RO system.
The rewards of routing RO waste water to the sink are, however, very great. The RO waste water can readily be used for things like thawing fish, thawing frozen products, rinsing vegetables, etc. It will be seen that, in the preferred embodiment of the present invention, it is sufficient merely to turn on a faucet valve on a console, or cabinet, in order to divert RO waste water into a sink for the above, and for other, purposes. Indeed, even the RO waste water will already have been filtered throughout both a sediment filter and a carbon filter, and--although containing such heavy materials as will not pass through an RO membrane--this "waste" water remains eminently useful for the above applications.
2.4 Integration of A Reverse Osmosis Water Purification System Into the Kitchen of the Future
It is desirable that a new embodiment of a reverse osmosis system suitably retro-fitted to existing kitchens, including the kitchens of restaurants, should be susceptible of integration with other equipments, and future equipments, of the kitchen. A new kitchen reverse osmosis water purification system should, as a minimum, be highly compatible with such other kitchen equipments as may required either the purified water or, more rarely, the waste water, that is produced by the RO system.
An example of such a device is the relatively new so-called "rice robot" for use in the kitchens of oriental restaurants. These "rice robots" are free-standing electrically-operated high-volume rice preparation and cooking appliances of considerable size and sophistication. They typically cost some tens of thousands of dollars U.S. each, circa 1996.
A "rice robot" typically serves to impeccably cleanse and cook successive batches each of some several liters of rice as is appropriate for, among other mass food service applications, oriental restaurants. Such modern (circa 1996) "rice robots" are sold, for example, by Kubota of Japan as models KR4501S and KR7201S. A very large, and economically significant, number of these units have reportedly been sold, reportedly more than twenty thousand (20,000).
These "rice robots" use the full normal amount of water required in the cleansing and cooking of rice. In accordance with the explanation in the preceding section 2.1 that this water should in certain portions of the process desirably be purified water, these modern machines are desirably suitably flow connected to the RO purified water supply of a modern (oriental) kitchen water station, or cabinet, or console. They are so connected in accordance with the present invention.
Yet another requirement for kitchen-wide integration of water services involves the occasional desire, or necessity, to store more purified RO water than may possibly be contained within such a (necessarily) small storage tank as is contained internally within the cabinet of a water station that fits within the modest volume of a wink--as will seen to be the case with the water station cabinet of the present invention. Accordingly, some accommodation of a modern kitchen water station to storing purified, RO, water in an auxiliary, remote, storage tank would be desirable.
It will momentarily be seen that the RO system in accordance with the present invention has a sophisticated in-unit, and external, water delivery system. From a storage tank built into the unit (in a position that will be seen be under a sink, and inside a cabinet), purified RO water will be seen to be deliverable out of either of two flow ports to any of a variety of other equipments and/or applications. For example, one of the output purified water ports can be routed to an additional pressurized storage tank for providing a backup supply of purified RO water, or for keeping additional water on hand in order to support more and/or different uses of the purified RO water.
2.5 Water Purified by Reverse Osmosis Substantially Alleviates the Precipitation of Calcium Deposits Onto Equipments Using the Purified Water
The aforementioned "rice robot" suffers greatly from calcium deposits precipitated from heated water. Similarly, steam tables, ice machines, steamers, proofing ovens and similar kitchen, restaurant and food service appliances--particularly as may use heated water, and as are predominantly used in the occident--are also subject to unsightly, and potentially functionally deleterious, deposits of calcium carbonate, or lime, from (heated) water.
Water purified by reverse osmosis substantially alleviates the precipitation of calcium deposits onto equipments using the purified water. Accordingly, the selective use of purified water in a kitchen offers advantages to machine function as well as to human taste.
2.6 A Kitchen Reverse Osmosis Water Purification System Would Desirably be Fool-Proof in Safety of Operation, Highly Reliable, and Easily Maintainable
It will momentarily be seen that the RO system in accordance with the present invention is operator-friendly, clearly indicating its operational status while being simply and straightforwardly controlled. The system is intrinsically safe not only in the RO process performed, but also in strict avoidance of any failure modes that might serve, as an ultimate negative consequence, to produce any output water (waste water as well as purified water) that had somehow been rendered unsafe, such as from an occurrence of bacterial growth.
Finally, the water station in accordance with the present invention will be seen to be highly maintainable. The preferred system will shortly be seen to have, for example, dual sediment filters with a diverter valve assembly. During processing water passes through a sediment filter which, after a period of time, gets dirty and clogged, slowing the flow of water. The RO water station and system in accordance with the present invention then permits, when the sediment filter gets dirty or clogged, that a valve between the two sediment filters should be manually turned, switching the system on-line to a clean sediment filter. The dirty sediment filter may then be changed without shutting down the system, and while the system remains running.